JBL K Potassium Test Set
Quick test to determine the potassium content in freshwater aquariums

  • For the perfect aquarium plant growth: determines the ideal potassium value to monitor the fertilisation of freshwater aquariums
  • Quick test: fill cuvette with sample water, add reagents, fill cloudy sample water into special glass vial until underlying cross is no longer visible, read the quantity you have filled. This value is equivalent to the potassium content in mg/l
  • Use: for the ideal setting of the potassium content for perfect plant growth, especially for sensitive plants
  • Online Laboratory: free analysis and recommendations for the water values you have measured
  • Package contents: 1 quick test, K Potassium Test Set. Contents for approx. 25 measurements. Incl. 2 reagents, special glass vial, syringe, dosing spoon and colour scale. Refill reagents available separately
Find out more
Recommended retail price incl. VAT
Available from your specialist dealer.
Dealer close to you
You can find this article at your specialist shop and online
Recommended retail price incl. VAT
Available from your specialist dealer.
Dealer close to you
You can find this article at your specialist shop and online
Product information

Healthy aquariums with conditions close to nature
The right water values are dependent on the fish stock and the plants in the aquarium. Even if the water looks clear it can be contaminated. With bad values diseases or algae can appear in the aquarium. To maintain a healthy aquarium with conditions close to nature it is important to check and adapt the water values regularly.

For each water analysis JBL provides water tests in the form of quick tests or colour change tests. These determine a certain value or several values in one go. With these water tests you can recognise algae problems and negative nitrate, nitrite, potassium, magnesium values etc.

Why test? Potassium is one of the macroelements which plants in freshwater absorb quickly and effectively within a few hours and can also store for a limited time. Growing plants require more potassium than other elements. As a result, potassium concentrations can drop to a minimum range, causing plant growth to stagnate, even if the aquarium water is fertilised regularly. Potassium levels in mains water are usually too low compared to those in natural biotopes, particularly with relation to calcium and magnesium concentrations.

Recommended potassium values:
Freshwater aquarium (community aquarium): 10-30 mg/l
Lake Malawi/Lake Tanganyika aquarium: 10-30 mg/l
Plant aquarium with few fish (aquascaping): 10-30 mg/l
Marine aquarium: the potassium content is not measurable with this test

You can analyse the water values you have measured in the JBL Online Laboratory free of charge and receive recommendations.

Details

JBL K Potassium Test Set

Art. no.:
2541100
EAN Code:
4014162254115
For:
25 Tests
Volume packaging:
0.800 l
Gross weight:
127.000 g
Net weight:
98 g
Weight factor:
1000
Size(l/h/w):
43/175/105 mm

JBL K Potassium Reagent

Art. no.:
2541200
EAN Code:
4014162254122
For:
Refill
Volume packaging:
0.450 l
Gross weight:
50.000 g
Net weight:
43 g
Weight factor:
1000
Size(l/h/w):
30/140/107 mm
FAQ
I have lost my colour chart. Can I download the colour chart for the test?

The colour cards are not available for download on the JBL homepage. For this a guaranteed true colour print is required, and you need a printer which can be re-calibrated before each printout. Most privately used printers are not accurate enough for this.

We will happily send you a new colour chart bundle with all individual colour charts for the JBL tests free of charge. Please forward the JBL customer service your address.

What can I do when the measured value of a water test falls outside the scale?

If one of your measurements reaches the end of the colour chart scale you can multiply the scale, by diluting the following tests with distilled water (e.g. JBL Dest).

Here’s how to do it: dilute the sample with distilled water and carry out the test once more.

Her’s how in greater detail:
JBL GH test kit: Instead of 5 ml use 10 ml aquarium water. Now 1 drop is equivalent to 0.5 dGH.
JBL KH test kit: Instead of 5 ml use 10 ml aquarium water. Now 1 drop is equivalent to 0.5 dGH.

Note: when using 10 ml sample water the colour development is weaker with the first drops than with 5 ml sample water. Put the measuring container on a white underlay for a better readability.

JBL NH4/NH3 Ammonium/Ammonia test kit, JBL NO2 Nitrite test kit, JBL Fe Iron test kit and JBL Cu Copper test kit:
2.5 ml sample + 2.5 ml dist. water: result times 2
1 ml sample + 4 ml dist. water: result times 5
0.5 ml sample + 4.5 ml dist. water: result times 10

NO3 Nitrate test kit, JBL SiO2 Silicate test kit, JBL PO4 Phosphate sensitive test kit and JBL Mg Magnesium test kit freshwater:
5 ml sample + 5 ml dist. water: result X 2
2 ml sample + 8 ml dist. water: result X 5
1 ml sample + 9 ml dist. water: result X 10

JBL PO4 Phosphate test kit koi high range:
2.5 ml sample + 2.5 ml dist. water: result X 2
1 ml sample + 4 ml dist. water: result X 5

JBL K Kalium test kit:
7.5 ml sample + 7.5 ml dist. water: result X 2
3.75 ml sample + 12.25 ml dist. water: result X 5
1.5 ml sample + 14.5 ml dist. water: result X 10

JBL CO2 direct test kit, JBL Ca Calcium test kit and JBL Mg+Ca Magnesium+Calcium test kit:
not required

Do my water tests still work although they have been open for nine months?

Basically a sealed test keeps longer than an open one. How much the shelf life is reduced depends crucially on the handling and the storage conditions of the reagents. It may happen that a reagent in a test that has been open for 9 months doesn’t indicate correctly any more. However, additional information is needed to answer this question properly.

Blog – Opinions & Experiences

07.09.2017

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Potassium is one of the macroelements which is quickly and effectively absorbed within a few hours and temporarily stored by plants in freshwater.

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05.11.2016

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22.10.2016

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28.09.2016

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The water in your aquarium is outstandingly significant because it is a life-giving element for fish and plants.

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18.09.2016

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Professional water analysis sounds very expensive. But the professional water testing in your aquarium or pond at home also works on a high level and above all it is simple and inexpensive.

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01.08.2016

Water values for water plants in detail

If we transfer this Liebig’s Law of the Minimum to the aquatic field it quickly becomes clear how important balanced fertilisation is for plant aquariums.

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25.07.2016

Plant care: How can water tests help?

Ideally water looks crystal-clear, yet pollutants are often invisible. That’s why clear water might still be toxic.

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01.04.2016

There’s more to fertilization than you’d think Part 2

Simply put, Liebig’s Law of the Minimum states that the growth of plants is limited by the scarcest resource. Adding a nutrient which already exists in abundance does not influence the growth.

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29.03.2016

Fertilization is not just fertilization Part 1

Unlike in natural waters, aquariums with fish mostly have a surplus of nutrients caused by feeding and the resulting fish excrement. Thus nitrates and phosphates in large (often too large!) quantities are available for the plants.

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29.08.2015

You ask, we answer: What’s the best way to fertilise an aquascape?

Dear Chris, dear Community, Thank you for your question. A luxuriant plant growth is based on the elements lighting, CO2 supply and an optimal fertilisation with nutrients.

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16.06.2015

JBL Potassium Test for salt water

There are hardly any marine water enthusiasts who don’t add trace elements to their aquariums. But many trace element supplements contain too much potassium, which in turn leads to green algae problems. With help of ...

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New JBL Water Tests – This is how the best test

Individualized and specific plant fertilization is not really possible without these new JBL water tests, because the consumption of potassium, magnesium and CO2 varies widely from plant species to plant species. ...

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Laboratories and calculators

Water Analysis Online Laboratory

Enter your water parameters and get an in-depth analysis of your values in a matter of seconds. You enter your water values – and we analyse! Here you have the opportunity to enter the measured water values directly into the JBL Online Laboratory. This will analyse your values and explain and submit corrective measures.
Worth reading

Aquarium problems

Are you faced with algae problems or don’t your aquarium plants grow well? Is the water cloudy or are your fish ill? Don’t your water parameters correspond to your expectations? Our team of experts has thoroughly analysed the problems that occur in the aquatic field and offers you solutions which really work.
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Instructions

safety instructions

spare parts
accessories
Safety information
safety information in accordance with GHS
Hazard symbol
  • GHS05
Risk phrase
H314: Causes severe skin burns and eye damage.
safety note
P103: Read label before use.
P280: Wear protective gloves/protective clothing/eye protection/face protection.
P305+P351+P338: IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P310a: Immediately call a POISON CENTER/doctor.
P101: If medical advice is needed, have product container or label at hand.
P102: Keep out of reach of children.
Signal word
Danger